Experimental procedures have been developed to simulate normal daily routines under the controlled conditions of a human residential laboratory. The daily routine includes a workshift, during which productive and accurate performance is required, as well as opportunities for social/recreational behavior during the evening, after the workshift. The residential laboratory provides an unique opportunity to investigate alcohol's effects on multiple dimensions of human behavior that have been shown to be differentially sensitive to a variety of pharmacological agents, under conditions that closely approximate the environmental context of the workplace. Five issues of critical importance to workplace policy will be addressed. First, a comprehensive determination of alcohol's affects on workplace-relevant behavior will be completed. To accomplish this objective, both acute and repeated alcohol dose affects on multiple behaviors, Including several that are necessary for safe and productive workplace performance, will be assessed under conditions approximating a typical workday. Second, the residual next day, or 'hang-over,' effects of alcohol use during nonwork time on these behaviors will be similarly analyzed. Third, the reliability and validity of techniques used to detect alcohol use in the workplace will be determined. Under the same conditions in which alcohol's effects on multiple behaviors is determined, breath and urine analysis, as well as testing with short-term performance batteries designed for the detection of performance impairment will be conducted. Alcohol's effects on these tests will be correlated with those on workshift behaviors to determine the reliability and predictive validity of alcohol-use detection batteries. Fourth, the relationship between environmental context and alcohol self-administration will be determined. The patterns of alcohol self-administration and dose preference will be measured under both naturalistic workplace and social/recreational contexts In order to determine whether these contexts influence alcohol's reinforcing effects. In addition, alcohol use will be measured when access to alcohol is unrestricted and when access is limited to those times in which alcohol is typically consumed in the workplace (i.e., at lunch and after work) to determine whether conditions of availability influence patterns of use. Fifth, across studies, the interaction between alcohol and social behavior will be determined under a variety of social contingencies and social contexts. Given the highly social nature of most workplace settings, social issues are of critical Importance to the workplace. The results of these studies will be important for the establishment of a data-based national policy on testing for alcohol use in the workplace and for the development of strategies for impacting alcohol use.